U.S. patent application number 15/983700 was filed with the patent office on 2019-11-21 for reamers for earth-boring applications having increased stability and related methods.
The applicant listed for this patent is Baker Hughes, a GE company, LLC. Invention is credited to Nathaniel R. Adams, Mitchell F. Marks, Kendrick D. McGee, Mitchell A. Rothe.
Application Number | 20190352972 15/983700 |
Document ID | / |
Family ID | 68534344 |
Filed Date | 2019-11-21 |
![](/patent/app/20190352972/US20190352972A1-20191121-D00000.png)
![](/patent/app/20190352972/US20190352972A1-20191121-D00001.png)
![](/patent/app/20190352972/US20190352972A1-20191121-D00002.png)
![](/patent/app/20190352972/US20190352972A1-20191121-D00003.png)
![](/patent/app/20190352972/US20190352972A1-20191121-D00004.png)
![](/patent/app/20190352972/US20190352972A1-20191121-D00005.png)
United States Patent
Application |
20190352972 |
Kind Code |
A1 |
Adams; Nathaniel R. ; et
al. |
November 21, 2019 |
REAMERS FOR EARTH-BORING APPLICATIONS HAVING INCREASED STABILITY
AND RELATED METHODS
Abstract
Reamer for earth-boring applications may include a body having a
longitudinal axis and a blade carried by the body. The blade may
include at least one cutting element located at a first radial
distance from the longitudinal axis and a gage pad located at a
second, smaller radial distance from the longitudinal axis. Methods
of enlarging pilot holes in earth formations utilizing reamers may
involve removing earth material from a sidewall of the pilot hole
utilizing at least one cutting element located at a first radial
distance from a longitudinal axis of a body of the reamer on a
blade of a reamer. The reamer may be stabilized by placing a gage
pad located on the blade in sliding contact with a portion of the
sidewall of the pilot hole, the gage pad located at a second,
smaller radial distance from the longitudinal axis
Inventors: |
Adams; Nathaniel R.; (The
Woodlands, TX) ; Rothe; Mitchell A.; (Montgomery,
TX) ; McGee; Kendrick D.; (Spring, TX) ;
Marks; Mitchell F.; (Youngsville, LA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Baker Hughes, a GE company, LLC |
Houston |
TX |
US |
|
|
Family ID: |
68534344 |
Appl. No.: |
15/983700 |
Filed: |
May 18, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 10/322 20130101;
E21B 12/00 20130101; E21B 7/28 20130101 |
International
Class: |
E21B 10/32 20060101
E21B010/32; E21B 7/28 20060101 E21B007/28; E21B 12/00 20060101
E21B012/00 |
Claims
1. A reamer for earth-boring applications, comprising: a body
having a longitudinal axis; and a blade carried by the body, the
blade comprising: at least one cutting element located at a first
radial distance from the longitudinal axis; and a gage pad located
at a second, smaller radial distance from the longitudinal
axis.
2. The reamer of claim 1, wherein the gage pad is located on an
axial side of the at least one cutting element configured to be
located closer to an earth-boring drill bit than the at least one
cutting element when the reamer is connected to a drill string.
3. The reamer of claim 1, further comprising another gage pad
located at a third radial distance farther from the longitudinal
axis than the second radial distance.
4. The reamer of claim 3, wherein the gage pad is positioned and
configured to contact, and slide against, a sidewall of a pilot
hole and the other gage pad is positioned and configured to
contact, and slide against, a sidewall of an enlarged borehole.
5. The reamer of claim 3, wherein the at least one cutting element
is located axially between the gage pad at the second radial
distance and the other gage pad at the third radial distance.
6. The reamer of claim 5, further comprising another cutting
element located on an axial side of the other gage pad at the third
radial distance opposite the at least one cutting element at the
first radial distance.
7. The reamer of claim 1, further comprising another cutting
element located on an axial side of the gage pad opposite the at
least one cutting element located at the first radial distance from
the longitudinal axis, the other cutting element located at a third
radial distance closer to the longitudinal axis than the first
radial distance.
8. The reamer of claim 1, wherein the first radial distance is at
least about 5% greater than the second radial distance.
9. The reamer of claim 1, wherein the blade is extensible from the
body and retractable toward the body and the at least one cutting
element does not extend beyond the body when the blade is in a
fully retracted state.
10. The reamer of claim 1, wherein the at least one cutting element
comprises a group of cutting elements having maximum radial
exposures located between the first radial distance and the second
radial distance.
11. An earth-boring tool, comprising: an earth-boring drill bit
comprising a gage region proximate an outer diameter of the
earth-boring drill bit; and a reamer connected to the earth-boring
drill bit, the reamer comprising: a body having a longitudinal
axis; and a blade carried by the body, the blade comprising: at
least one cutting element located at a first radial distance from
the longitudinal axis; and a gage pad located at a second, smaller
radial distance from the longitudinal axis, the second radial
distance being at least substantially equal to the outer diameter
of the earth-boring drill bit.
12. The earth-boring tool of claim 11, further comprising another
gage pad located at a third radial distance farther from the
longitudinal axis than the second radial distance.
13. The earth-boring tool of claim 12, wherein the at least one
cutting element is located axially between the gage pad at the
second radial distance and the other gage pad at the third radial
distance.
14. The earth-boring tool of claim 13, further comprising another
cutting element located on an axial side of the other gage pad at
the third radial distance opposite the at least one cutting element
at the first radial distance.
15. The earth-boring tool of claim 11, further comprising another
cutting element located on an axial side of the gage pad opposite
the at least one cutting element located at the first radial
distance from the longitudinal axis, the other cutting element
located at a third radial distance closer to the longitudinal axis
than the first radial distance.
16. A method of enlarging a pilot hole in an earth formation
utilizing a reamer, comprising: enlarging a pilot hole by removing
earth material from a sidewall of the pilot hole to form an
enlarged borehole utilizing at least one cutting element located on
a blade of a reamer, the at least one cutting element located at a
first radial distance from a longitudinal axis of a body of the
reamer; and stabilizing the reamer by placing a gage pad located on
the blade of the reamer in sliding contact with a portion of the
sidewall of the pilot hole, the gage pad located at a second,
smaller radial distance from the longitudinal axis.
17. The method of claim 16, wherein stabilizing the reamer further
comprises placing another gage pad located on the blade of the
reamer in sliding contact with a portion of the sidewall of the
enlarged borehole, the other gage pad located at a third radial
distance farther from the longitudinal axis than the second radial
distance.
18. The method of claim 17, further comprising back-reaming the
enlarged borehole utilizing another cutting element located on an
axial side of the other gage pad at the third radial distance
opposite the at least one cutting element at the first radial
distance.
19. The method of claim 16, further comprising clearing earth
material from the sidewall of the pilot hole utilizing another
cutting element located on an axial side of the gage pad opposite
the at least one cutting element located at the first radial
distance from the longitudinal axis, the other cutting element
located at a third radial distance closer to the longitudinal axis
than the first radial distance.
20. The method of claim 16, wherein placing the gage pad in sliding
contact with the portion of the sidewall of the pilot hole
comprises extending the blade from a retracted state to an extended
state.
Description
FIELD
[0001] This disclosure relates generally to earth-boring tools and
methods of making and using earth-boring tools. More specifically,
disclosed embodiments relate to reamers for earth-boring
applications that may increase stability during drilling, which may
improve borehole quality, increase earth-boring efficiency, and
increase useful lift of earth-boring tools, among other
benefits.
BACKGROUND
[0002] When deployed in earth-boring applications, reamers are
typically used to enlarge a borehole. For example, a drill string
may include a so-called "pilot" drill bit at a leading end of the
drill string and a reamer trailing behind the drill bit along the
drill string. The reamer may include blades fixed at or expandable
to an outer diameter greater than the outer diameter of the drill
bit, and greater than the outer diameter of the borehole located on
the same side of the reamer as the drill bit. In other
applications, a reamer may be introduced into an already-formed
borehole. The blades may have a cutting structure to engage and cut
away earth material from the sidewalls of the borehole, enlarging
the diameter of the borehole. The blades of reamers may be, for
example, fixed at an outer diameter concentric with or eccentric to
the drill bit, or expandable from a retracted position where the
outer diameter is at less than or equal to the diameter of the
drill bit to an expanded position where the outer diameter is
greater than the diameter of the drill bit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] While this disclosure concludes with claims particularly
pointing out and distinctly claiming specific embodiments, various
features and advantages of embodiments within the scope of this
disclosure may be more readily ascertained from the following
description when read in conjunction with the accompanying
drawings, in which:
[0004] FIG. 1 is an enlarged, partial cross-sectional side view of
a reamer for earth-boring applications in a retracted state;
[0005] FIG. 2 is an enlarged, partial cross-sectional side view of
the reamer of FIG. 1 in an extended state;
[0006] FIG. 3 is an enlarged side view of a blade of the reamers of
FIGS. 1 and 2;
[0007] FIG. 4 is a partial cross-sectional, schematic side view of
a drill string including the reamer of FIG. 1 in the retracted
state; and
[0008] FIG. 5 is a partial cross-sectional, schematic side view of
the drill string of FIG. 4 with the reamer in an extended
state.
DETAILED DESCRIPTION
[0009] The illustrations presented in this disclosure are not meant
to be actual views of any particular earth-boring tool, reamer, or
component thereof, but are merely idealized representations
employed to describe illustrative embodiments. Thus, the drawings
are not necessarily to scale.
[0010] Disclosed embodiments relate generally to reamers for
earth-boring applications that may increase stability during
drilling, which may improve borehole quality, increase earth-boring
efficiency, and increase useful lift of earth-boring tools, among
other benefits. More specifically, disclosed are embodiments of
blades for reamers for earth-boring applications that may include a
first, stabilizing portion having an outer diameter less than an
outer diameter of a second, reaming portion of the blades.
[0011] As used herein, the terms "substantially" and "about" in
reference to a given parameter, property, or condition means and
includes to a degree that one of ordinary skill in the art would
understand that the given parameter, property, or condition is met
with a degree of variance, such as within acceptable manufacturing
tolerances. For example, a parameter that is substantially or about
a specified value may be at least about 90% the specified value, at
least about 95% the specified value, at least about 99% the
specified value, or even at least about 99.9% the specified
value.
[0012] The term "earth-boring tool," as used herein, means and
includes any type of bit or tool used for drilling during the
formation or enlargement of a wellbore in a subterranean formation.
For example, earth-boring tools include fixed cutter bits, core
bits, eccentric bits, bicenter bits, reamers, mills, hybrid bits
including both fixed and rotatable cutting structures, and other
drilling bits and tools known in the art.
[0013] As used herein, the term "earth-boring drill bit" means and
includes any type of bit or tool used for drilling during the
formation of a wellbore in a subterranean formation. For example,
earth-boring tools include fixed cutter bits, core bits, eccentric
bits, bicenter bits, hybrid bits including both fixed and rotatable
cutting structures, and other drilling bits known in the art.
[0014] The term "gage pad," as used herein, means and includes any
component sized, shaped, positioned, and having a durability
configured for placement in sliding contact with a sidewall of a
borehole in an earth formation. For example, gage pads include
outer surfaces of materials integral to a body of a component of an
earth-boring tool, separately formed panels of material secured to
a body of a component of an earth-boring tool, or materials
deposited on a body of a component of an earth-boring tool (e.g.,
hardfacing). By way of additional example, structures and
components configured to remove earthen material, such as, for
example, cutting elements, cutting inserts,
[0015] FIG. 1 is an enlarged, partial cross-sectional side view of
a reamer 100 for earth-boring applications in a retracted state.
The reamer 100 may include, for example, a body 102 and at least
one blade 104 carried by the body 102. The body 102 may include a
tubular member configured to support other components of the reamer
100 thereon. The body 102 may have a leading end 106 and a trailing
end 108, each configured for connection to another component of a
drill string, such as, for example, by an American Petroleum
Institute (API) standard connection. A longitudinal axis 110 of the
body 102 may extend between the leading end 106 and the trailing
end 108 proximate an average geometric center of the body 102 from
the leading end 106 to the trailing end 108. A passageway 112 may
extend axially through the body 102 between the leading end 106 and
the trailing end 108 to enable circulating drilling fluid to flow
through the reamer 100.
[0016] In embodiments where the reamer 100 is configured as an
expandable reamer, such as that depicted in FIG. 1, the body 102
may support an actuation mechanism 114 configured to move each
blade 104 at least from the retracted state shown in FIG. 1 to the
extended state shown in FIG. 2, and optionally back to the
retracted state and/or back and forth between the retracted state
and the extended state. Any actuation mechanism 114 may be employed
with reamers 100 having a blade 104 or blades 104 configured in
accordance with this disclosure. As a specific, nonlimiting
example, the actuation mechanism 114 shown and described in U.S.
Pat. No. 8,960,333, issued Feb. 24, 2015, to Radford et al.
Briefly, operation of the actuation mechanism 114 may involve
releasing one or more obstructions (e.g., balls) into the
circulating drilling fluid, which may lodge into one or more
complementary components of the actuation mechanism 114, causing
pressure of the drilling fluid to act on and move those components.
Movement of the components of the actuation mechanism 114 may cause
corresponding movement of the blade 104 or blades 104, enabling
extension and/or retraction of the blade 104 or blades 104. In
other embodiments, reamers having a blade 104 or blades 104 in
accordance with this disclosure may not be expandable (e.g., may be
configured as "concentric" reamers or as "eccentric reamers,
commonly termed "reamer wings"), having a blade 104 or blades 104
fixed in the extended state depicted in FIG. 2.
[0017] The blade 104 or blades 104 supported by the body 102 of the
reamer 100 may include a first portion 116 located a first radial
distance RD.sub.1 from the longitudinal axis 110 greater than a
second radial distance RD.sub.2 from the longitudinal axis 110 to a
second portion 118 of the blade 104 or blades 104. The first radial
distance RD.sub.1 and the second radial distance RD.sub.2 may be
measured from the longitudinal axis 110, in a direction at least
substantially perpendicular to the longitudinal axis 110, to a
radially outermost point on an outer surface 124 of the blade 104
or on a gage pad 120 or cutting element 122 carried by the blade
104. The first portion 116 may be located at a radially outer
surface of the blade 104 and may include one or more cutting
elements 122 secured to the blade 104 and configured and positioned
to engage with, and remove, earth material from a sidewall of the
pilot hole to form an enlarged borehole. The second portion 118 may
be located at a radially outer surface of the blade 104 and may
include one or more gage pads 120 configured and positioned to
contact, and slide against, the wall of a pilot hole in an earth
formation to stabilize the reamer 100.
[0018] The first radial distance RD.sub.1 may be, for example, at
least about 5% greater than the second radial distance RD.sub.2.
More specifically, the first radial distance RD.sub.1 may be, for
example, between about 10% and about 50% greater than the second
radial distance RD.sub.2. As a specific, nonlimiting example, the
first radial distance RD.sub.1 may be, for example, between about
15% and about 40% greater than the second radial distance RD.sub.2
(e.g., about 20% greater, about 25% greater, or about 30%
greater).
[0019] When the blade 104 or blades 104 are in the retracted state,
at least the second portion 118 may be located within a radial
extent of the body 102. For example, a third radial distance
RD.sub.3 from the longitudinal axis 110 to a radially farthest
point on the outer surface 124 of the body 102 may be greater than
the second radial distance RD.sub.2. More specifically, the first
portion 116 and the second portion 118 may be located within the
radial extent of the body 102. As a specific, nonlimiting example,
the third radial distance RD.sub.3 from the longitudinal axis 110
to the radially farthest point on the outer surface 124 of the body
102 may be greater than the first radial distance RD.sub.1 and the
second radial distance RD.sub.2. Keeping at least a portion, or an
entirety, of the blade 104 or blades 104 within the radial extent
of the body 102 while the reamer 100 is in the extended state may
enable the reamer to be tripped into a borehole (e.g., through a
casing or liner string lining a borehole) while reducing the
likelihood that the blade 104 or blades 104, including the gage pad
120 or gage pads 120 and the cutting element 122 or cutting
elements 122 thereof, may undesirably contact the sidewall of the
borehole.
[0020] FIG. 2 is an enlarged, partial cross-sectional side view of
the reamer 100 of FIG. 1 in an extended state. When the actuation
mechanism 114 is activated, the blade 104 or blades 104 may extend
radially outward from the retracted state depicted in FIG. 1 toward
a radially outermost position in the extended state depicted in
FIG. 2. When the reamer 100 is in the extended state, the first
radial distance RD.sub.1 from the longitudinal axis 110 of the body
102 to the first portion 116 of the blade 104 may be greater than
the first radial distance RD.sub.1 was when the reamer 100 was in
the retracted state. The second radial distance RD.sub.2 from the
longitudinal axis 110 of the body 102 to the second portion 118 of
the blade 104 may likewise be greater than the second radial
distance RD.sub.2 was when the reamer 100 was in the retracted
state. The second radial distance RD.sub.2 may remain less than the
first radial distance RD.sub.1 in both the retracted state and the
extended state.
[0021] When the blade 104 or blades 104 are in the extended state,
at least a section of the first portion 116 may be located radially
beyond the radial extent of the body 102. For example, the third
radial distance RD.sub.3 from the longitudinal axis 110 to the
radially farthest point on the outer surface 124 of the body 102
may be less than the first radial distance RD.sub.1. More
specifically, an entirety of the first portion 116 may be located
beyond the radial extent of the body 102 and the second portion 118
may be located radially beyond, or at least substantially flush
with, the radial extent of the body 102. As a specific, nonlimiting
example, the third radial distance RD.sub.3 from the longitudinal
axis 110 to the radially farthest point on the outer surface 124 of
the body 102 may be less than the first radial distance RD.sub.1
and the second radial distance RD.sub.2. When the blade 104 or
blades 104 are in the extended state, the first portion 116 may be
positioned to engage with, and cut away, earth material from the
sidewall of a pilot hole to form an enlarged borehole and the
second portion 118 may be positioned to contact, and slide against,
the sidewall of the pilot hole to stabilize the reamer.
[0022] FIG. 3 is an enlarged side view of a blade 104 of the reamer
100 of FIGS. 1 and 2. The blade 104 may include an inner surface
126 located on a side of the blade 104 opposite the outer surface
124, and configured to be positioned proximate the longitudinal
axis 110 when the blade 104 is installed in a reamer 100 (see FIGS.
1, 2). The inner surface 126 may be sloped, such that the inner
surface 126 at an axially leading end 128 of the blade 104 is
located radially farther from the first portion 116 and the second
portion 118 than the inner surface 126 at an axially trailing end
130 of the blade 104. A fourth radial distance RD.sub.4 between the
inner surface 126 at the axially leading end 128 of the blade 104
and the first portion 116 may be greater than a fifth radial
distance RD.sub.5 between the inner surface 126 at the axially
leading end 128 of the blade 104 and the second portion 118. The
fourth radial distance RD.sub.4 and the fifth radial distance
RD.sub.5 may be measured from the inner surface 126 at the axially
leading end 128 of the blade 104, in a direction at least
substantially normal to a direction of intended rotation of the
blade 104, to a radially outermost point on an outer surface 124 of
the blade 104 or on a gage pad 120 or cutting element 122 carried
by the blade 104.
[0023] The fourth radial distance RD.sub.4 may be, for example,
about at least about 5% greater than the fifth radial distance
RD.sub.5. More specifically, the fourth radial distance RD.sub.4
may be, for example, between about 10% and about 60% greater than
the fifth radial distance RD.sub.5. As a specific, nonlimiting
example, the fourth radial distance RD.sub.4 may be, for example,
between about 15% and about 50% greater than the fifth radial
distance RD.sub.5 (e.g., about 20% greater, about 30% greater, or
about 40% greater).
[0024] As shown in FIG. 3, the first portion 116 may be located
axially adjacent to the second portion 118, such that the
stabilization enabled by the first portion 116 may be located
axially closer to the borehole enlargement enabled by the second
portion 118, when compared to conventional solutions for
stabilizing earth-boring reamers. For example, an axial border 132
between the first portion 116 and the second portion 118 may be
formed by a first cutting element 122 of the first portion 116
located axially above a gage pad 120 of the second portion 118 or a
change in direction of the outer surface 124 from at least
substantially parallel to a direction of intended advancement of
the blade 104 during reaming to an oblique angle with the direction
of intended advancement of the blade 104. The gage pad 120 may be
located on an axial side of the cutting element 122 configured to
be located closer to an earth-boring drill bit than the cutting
element 122 when blade 104 is installed in a reamer 100 (see FIGS.
1, 2) and the reamer 100 (see FIGS. 1, 2) is connected to a drill
string.
[0025] To better facilitate enlarging the pilot hole against the
wall of which the gage pad 120 of the second portion 118 may slide,
the cutting elements 122 of the first portion 116 may be arranged
in a group having maximum radial exposures above the outer surface
124 of the blade 104 located between the first radial distance
RD.sub.1 and the second radial distance RD.sub.2. The group of
cutting elements 122 may collectively form a cutting profile shaped
and positioned to progressively remove earth material from the
sidewall of a pilot hole radially outward to form an enlarged
borehole.
[0026] In some embodiments, such as that shown in FIG. 3, the blade
104 may include another gage pad 134 located at a sixth radial
distance RD.sub.6 farther from the inner surface 126 than the fifth
radial distance RD.sub.5, and at a seventh radial distance RD.sub.7
farther from the longitudinal axis 110 than the second radial
distance RD.sub.2. The sixth radial distance RD.sub.6 may be, for
example, at least substantially equal to, or less than, the fourth
radial distance RD.sub.4, and the seventh radial distance RD.sub.7
may be, for example, at least substantially equal to, or less than,
the first radial distance RD.sub.1. The other gage pad 134 may be
configured and positioned to contact, and slide against, a sidewall
of an enlarged borehole formed by the cutting elements 122 of the
first portion 116 to stabilize the reamer 100 when enlarging the
pilot hole. The other gage pad 134 may be located on an axial side
of the first portion 116 and its associated cutting elements 122
opposite a side on which the second portion 118 and its associated
gage pad 120 are located, such that the cutting elements may be
located axially between the gage pad 120 at the second radial
distance RD.sub.2 and the other gage pad 134 at the seventh radial
distance RD.sub.7.
[0027] In some embodiments, such as that shown in FIG. 3, the blade
104 may include at least another cutting element 136 located on an
axial side of the other gage pad 134 at the seventh radial distance
RD.sub.7 opposite an axial side on which the cutting elements 122
at the fifth radial distance RD.sub.5. The other cutting element
136 or cutting elements 136 secured to the blade 104 may be
positioned, oriented, and configured to engage with, and remove,
earth material from a sidewall of the pilot hole or of the enlarged
borehole to form an enlarged borehole when back-reaming or to
reduce the likelihood that unintended contact with the sidewall of
the enlarged borehole will cause the reamer 100 (see FIGS. 1, 2) to
become jammed or otherwise stuck in the borehole. For example, the
reamer 100 (see FIGS. 1, 2) may be placed into a pilot hole in an
earth formation in a retracted state, tripped beyond a casing
lining the pilot hole, placed in an extended state to cause the
other cutting elements 136 to contact the sidewall of the pilot
hole, and rotated while moving the reamer 100 (see FIGS. 1, 2) back
toward the surface. The other cutting elements 136 may remove earth
material from the sidewall of the pilot hole to form an enlarged
borehole. As another example, the cutting elements 122 of the
reamer 100 (see FIGS. 1, 2) may be used to enlarge a borehole while
the blades 104 are in the extended state, the blades 104 may remain
in an extended state, and the reamer 100 (see FIGS. 1, 2) may be
rotated while moving back toward the surface. The other cutting
elements 136 may remove earth material from the sidewall of the
enlarged borehole to reduce the risk of jamming.
[0028] In some embodiments, such as that shown in FIG. 3, the blade
104 may include still another cutting element 138 located on an
axial side of the gage pad 120 opposite the cutting elements 122
located at the first radial distance RD.sub.1 from the longitudinal
axis 110. The one or more other cutting elements 138 may be located
at an eighth radial distance RD.sub.8 closer to the longitudinal
axis 110 than the first radial distance RD.sub.1, and a ninth
radial distance RD.sub.9 closer to the inner surface 126 than the
fourth radial distance RD.sub.4. More specifically, the eighth
radial distance RD.sub.8 at which the other cutting elements 138
are located from the longitudinal axis 110 may be at least
substantially equal to, or greater or less than, the second radial
distance RD.sub.2 at which the gage pad 120 is located from the
longitudinal axis 110 and less than the first radial distance
RD.sub.1 at which the cutting elements 122 associated with the
first portion 116 are located from the longitudinal axis 110. The
other cutting element 138 or cutting elements 138 secured to the
blade 104 may be positioned, oriented, and configured to engage
with, and remove, earth material from a sidewall of the pilot hole
to reduce the likelihood that unintended contact with the sidewall
of the pilot hole will cause the reamer 100 (see FIGS. 1, 2) to
become jammed or otherwise stuck in the borehole. For example, the
cutting elements 122 of the reamer 100 (see FIGS. 1, 2) may be used
to enlarge a borehole while the blades are in the extended state,
and the other cutting elements 138 may remove earth material from
the sidewall of the pilot hole to reduce the risk of jamming while
the gage pad 120 stabilizes the reamer by being placed in sliding
contact with the sidewall of the pilot hole.
[0029] The blade 104, and its various components, may be made from
materials suitable for use in the downhole environment. For
example, the blade 104 and its components may include steel and/or
metallic-ceramic composite materials (i.e., cermets). More
specifically, the blade 104 may include a steel alloy or a metal-
or metal-alloy-bound tungsten carbide particle-matrix composite
material, and may be formed by casting or forging of the metal or
metal alloy, infiltration of ceramic particles utilizing a metal
matrix material, or other manufacturing processes known in the art.
The gage pads 120 and the other gage pads 134 may include, for
example, hardfacing material (i.e., abrasion-resistant particles
bound in a metal or metal-alloy matrix material) and/or
metallic-ceramic composite materials, and may be deposited on, or
separately formed and attached to, the relevant surfaces and
locations on the blade 104 by welding or other processes known in
the art. The cutting elements 122, other cutting elements 136, and
still other cutting elements 138 may include a unitary body of
material or a substrate with a cutting table secured to an end of
the substrate, and may be placed within pockets formed in the
blades 104 and secured thereto (e.g., by a weld or braze), may be
cast into the pockets during formation of the blades 104, or
attached to the blades 104 by other processes known in the art.
[0030] FIG. 4 is a partial cross-sectional, schematic side view of
a drill string 140 including the reamer 100 of FIG. 1 in the
retracted state. When using the reamer 100 to enlarge a pilot hole
142, the drill string 140 may be lowered into the earth formation
144. In the embodiment shown in FIG. 4, the pilot hole 142 has been
preformed, and is lined with a casing 146 that the drill string is
moved through. In other embodiments, the pilot hole may be formed
concurrently during reaming and enlargement of the pilot hole to
form an enlarged borehole. The drill string 140 may include, for
example, one or more sections of drill pipe 148, the reamer 100
located between a leading end 150 of the drill string 140 and the
surface 152, and an earth-boring drill bit 154 located at the
leading end 150 of the drill string 140.
[0031] When the reamer 100 is in the retracted state, at least a
portion, and up to an entirety, of each blade 104 may be located
within the radial confines of the body 102. More specifically, at
least the cutting elements 138 located at the axially leading end
128 of the blades 104, the gage pads 120 located axially adjacent
to the cutting elements 138 on the blades 104 and at least some of
the cutting elements 122 located axially adjacent to the gage pads
120 on an axial side of the gage pads 120 opposite the axially
leading end 128 may be located radially within the outer surface of
the body 102. In some embodiments, all of the cutting elements 122
located axially adjacent to the gage pads 120, the other gage pads
134 located axially adjacent to the cutting elements 122 on an
axial side of the cutting elements 122 opposite the gage pads 120,
and the other cutting elements 136 located adjacent to the other
gage pads 134 on an axial side of the other gage pads 134 opposite
the cutting elements 122 proximate the axially trailing end 130 of
the blade may be located radially within the body 102.
[0032] While in the retracted state, the drill string 140,
including the earth-boring drill bit 154 and the reamer 100 may be
advanced to a desired position within the pilot hole 142. For
example, the drill string 140 may be advanced into the pilot hole
142 until at least the reamer 100 has advanced beyond a distal end
of the casing 146.
[0033] FIG. 5 is a partial cross-sectional, schematic side view of
the drill string 140 of FIG. 4 with the reamer 100 in an extended
state. The reamer 100 may be placed in the extended state, for
example, after the reamer 100 has been positioned beyond the distal
end 156 of the casing 146, or simply after the reamer 100 has
entered the pilot hole 142 in embodiments where enlargement occurs
concurrently with formation of the pilot hole 142. When the reamer
100 is placed in the extended state, the cutting elements 122 may
engage with, and remove earth material from, the sidewall 158 of
the pilot hole 142. A radially outermost one of the cutting
elements 122, which may be define the fourth radial distance
RD.sub.4 and the fifth radial distance RD.sub.5 (see FIG. 3), may
be the first feature of the blade 104 to contact the sidewall 158
of the pilot hole 142 when transitioning from the retracted state
to the extended state. The cutting elements 122 may cooperatively
increase the diameter of the pilot hole 142 to form an enlarged
borehole 160.
[0034] The reamer 100 may be stabilized against the sidewall 158 of
the pilot hole 142 by the gage pads 120. For example, extension of
the blades 104 to the extended state may bring the gage pads 120
into sliding contact with the sidewall 158 of the pilot hole 142.
As the drill string 140 is rotated, causing the reamer 100 to
rotate within the pilot hole 142 and the enlarged borehole 160, the
non-aggressive contact between the gage pads 120 and the sidewall
158 of the pilot hole 142 may reduce vibrations and non-concentric
rotation of the drill string 140. Because the gage pads 120 are
located closer to the body 102 of the reamer 100 than the cutting
elements 122, particularly when the blades 104 are in the extended
state, the gage pads 120 may come into contact with the sidewall
158 of the pilot hole 142 after the cutting elements 122 as the
blades 104 move from the retracted state to the extended state.
[0035] In embodiments where the blades 104 include the other gage
pads 134, the reamer 100 may be further stabilized against the
sidewall 162 of the enlarged borehole 160 by the other gage pads
134. For example, extension of the blades 104 to the extended state
may bring the other gage pads 134 into sliding contact with the
sidewall 162 of the enlarged borehole 160. As the reamer 100
rotates within the pilot hole 142 and the enlarged borehole 160,
the non-earth-removing contact between the other gage pads 134 and
the sidewall 162 of the enlarged borehole 160 may further reduce
vibrations and non-concentric rotation of the drill string 140.
Because the other gage pads 120 are located farther from the body
102 of the reamer 100 than the gage pads 120, particularly when the
blades 104 are in the extended state, the other gage pads 134 may
come into contact with the sidewall 162 of the enlarged borehole
160 before the gage pads 120 come into contact with the sidewall
158 of the pilot hole 142 (e.g., between when the cutting elements
122 contact the sidewall 158 and the gage pads 120 contact the
sidewall 158) as the blades 104 move from the retracted state to
the extended state.
[0036] In embodiments where the blades 104 include the other
cutting elements 136, the other cutting elements 136 may be used to
back-ream the pilot hole 142, to reduce the risk of jamming while
the reamer 100 is removed from the enlarged borehole 160, or both.
For example, extension of the blades 104 to the extended state may
bring the other cutting elements 136 into cutting engagement with
the sidewall 158 of the pilot hole 142. As the reamer 100 rotates
within the pilot hole 142 during back-reaming, or within the
enlarged borehole 160 during extraction, and the reamer 100 is
moved closer to the surface 152, the aggressive contact between the
other cutting elements 136 and the sidewall 158 of the pilot hole
142 may remove earth material from the sidewall 158 of the pilot
hole 142 to form the enlarged borehole 160 (e.g., between where the
blades 104 are moved to the extended state and the distal end 156
of the casing 146), or from the sidewall 162 of the enlarged
borehole 160 to reduce the risk of jamming. Because the other
cutting elements 136 are located farther from the body 102 of the
reamer 100 than the gage pads 120, particularly when the blades 104
are in the extended state, the other cutting elements 136 may come
into contact with the sidewall 162 of the enlarged borehole 160
before the gage pads 120 come into contact with the sidewall 158 of
the pilot hole 142 (e.g., at least substantially at the same time
as, or after, the cutting elements 122 contact the sidewall 122) as
the blades 104 move from the retracted state to the extended
state.
[0037] In embodiments where the blades 104 include the still other
cutting elements 138, the still other cutting elements 138 may be
used to reduce the risk of jamming while the reamer 100 is advanced
into the pilot hole 142. For example, extension of the blades 104
to the extended state may bring the still other cutting elements
138 into cutting engagement with the sidewall 158 of the pilot hole
142. As the reamer 100 rotates within the pilot hole 142 and the
enlarged borehole 160, the earth-removing contact between the still
other cutting elements 138 and the sidewall 158 of the pilot hole
142 may remove earth material from the sidewall 158 of the pilot
hole 142 to reduce the risk of jamming. Because the still other
cutting elements 138 are located closer to the body 102 of the
reamer 100 than the cutting elements 122, particularly when the
blades 104 are in the extended state, the still other cutting
elements 138 may come into contact with the sidewall 158 of the
pilot hole 142 after the cutting elements 122 come into contact
with the sidewall 158 of the pilot hole 142 (e.g., at least
substantially at the same time as, before, or after the gage pads
120 com into contact with the sidewall 158 of the pilot hole 142)
as the blades 104 move from the retracted state to the extended
state.
[0038] By placing the gage pads 120 on the blades 104 of the reamer
100 themselves, positioning, the gage pads 120 axially proximate to
(e.g., directly axially adjacent to) the cutting elements 122 used
to enlarge the pilot hole 142, and otherwise configuring the gage
pads 120 to stabilize the blades 104 against the pilot hole 142,
the gage pads 120 may better stabilize the reamer 100. Stability
during earth-boring operations in general, and reaming in
particular, provides many benefits, including reducing wear on the
components of the drill string 140, reduced energy input per unit
of distance traveled downhole, and improved quality of the enlarged
borehole 160 (e.g., smoother sidewalls 162, reduced risk of
collapse, etc.).
[0039] Additional, nonlimiting embodiments within the scope of this
disclosure include the following:
[0040] Embodiment 1: A reamer for earth-boring applications,
comprising: a body having a longitudinal axis; and a blade carried
by the body, the blade comprising: at least one cutting element
located at a first radial distance from the longitudinal axis; and
a gage pad located at a second, smaller radial distance from the
longitudinal axis.
[0041] Embodiment 2: The reamer of Embodiment 1, wherein the gage
pad is located on an axial side of the at least one cutting element
configured to be located closer to an earth-boring drill bit than
the at least one cutting element when the reamer is connected to a
drill string.
[0042] Embodiment 3: The reamer of Embodiment 1 or Embodiment 2,
further comprising another gage pad located at a third radial
distance farther from the longitudinal axis than the second radial
distance.
[0043] Embodiment 4: The reamer of Embodiment 3, wherein the gage
pad is positioned and configured to contact, and slide against, a
sidewall of a pilot hole and the other gage pad is positioned and
configured to contact, and slide against, a sidewall of an enlarged
borehole.
[0044] Embodiment 5: The reamer of Embodiment 3, wherein the at
least one cutting element is located axially between the gage pad
at the second radial distance and the other gage pad at the third
radial distance.
[0045] Embodiment 6: The reamer of Embodiment 5, further comprising
another cutting element located on an axial side of the other gage
pad at the third radial distance opposite the at least one cutting
element at the first radial distance.
[0046] Embodiment 7: The reamer of any one of Embodiments 1 through
6, further comprising another cutting element located on an axial
side of the gage pad opposite the at least one cutting element
located at the first radial distance from the longitudinal axis,
the other cutting element located at a third radial distance closer
to the longitudinal axis than the first radial distance.
[0047] Embodiment 8: The reamer of any one of Embodiments 1 through
7, wherein the first radial distance is at least about 5% greater
than the second radial distance.
[0048] Embodiment 9: The reamer of any one of Embodiments 1 through
8, wherein the blade is extensible from the body and retractable
toward the body and the at least one cutting element does not
extend beyond the body when the blade is in a fully retracted
state.
[0049] Embodiment 10: The reamer of any one of Embodiments 1
through 9, wherein the at least one cutting element comprises a
group of cutting elements having maximum radial exposures located
between the first radial distance and the second radial
distance.
[0050] Embodiment 11: An earth-boring tool, comprising: an
earth-boring drill bit comprising a gage region proximate an outer
diameter of the earth-boring drill bit; and a reamer connected to
the earth-boring drill bit, the reamer comprising: a body having a
longitudinal axis; and a blade carried by the body, the blade
comprising: at least one cutting element located at a first radial
distance from the longitudinal axis; and a gage pad located at a
second, smaller radial distance from the longitudinal axis, the
second radial distance being at least substantially equal to the
outer diameter of the earth-boring drill bit.
[0051] Embodiment 12: The earth-boring tool of Embodiment 11,
further comprising another gage pad located at a third radial
distance farther from the longitudinal axis than the second radial
distance.
[0052] Embodiment 13: The earth-boring tool of Embodiment 12,
wherein the at least one cutting element is located axially between
the gage pad at the second radial distance and the other gage pad
at the third radial distance.
[0053] Embodiment 14: The earth-boring tool of Embodiment 13,
further comprising another cutting element located on an axial side
of the other gage pad at the third radial distance opposite the at
least one cutting element at the first radial distance.
[0054] Embodiment 15: The reamer of any one of Embodiments 11
through 14, further comprising another cutting element located on
an axial side of the gage pad opposite the at least one cutting
element located at the first radial distance from the longitudinal
axis, the other cutting element located at a third radial distance
closer to the longitudinal axis than the first radial distance.
[0055] Embodiment 16: A method of enlarging a pilot hole in an
earth formation utilizing a reamer, comprising: enlarging a pilot
hole by removing earth material from a sidewall of the pilot hole
to form an enlarged borehole utilizing at least one cutting element
located on a blade of a reamer, the at least one cutting element
located at a first radial distance from a longitudinal axis of a
body of the reamer; and stabilizing the reamer by placing a gage
pad located on the blade of the reamer in sliding contact with a
portion of the sidewall of the pilot hole, the gage pad located at
a second, smaller radial distance from the longitudinal axis.
[0056] Embodiment 17: The method of Embodiment 16, wherein
stabilizing the reamer further comprises placing another gage pad
located on the blade of the reamer in sliding contact with a
portion of the sidewall of the enlarged borehole, the other gage
pad located at a third radial distance farther from the
longitudinal axis than the second radial distance.
[0057] Embodiment 18: The method of Embodiment 17, further
comprising back-reaming the enlarged borehole utilizing another
cutting element located on an axial side of the other gage pad at
the third radial distance opposite the at least one cutting element
at the first radial distance.
[0058] Embodiment 19: The method of any one of Embodiments 16
through 18, further comprising clearing earth material from the
sidewall of the pilot hole utilizing another cutting element
located on an axial side of the gage pad opposite the at least one
cutting element located at the first radial distance from the
longitudinal axis, the other cutting element located at a third
radial distance closer to the longitudinal axis than the first
radial distance.
[0059] Embodiment 20: The method of any one of Embodiments 16
through 19, wherein placing the gage pad in sliding contact with
the portion of the sidewall of the pilot hole comprises extending
the blade from a retracted state to an extended state.
[0060] Embodiment 21: The method of Embodiment 20, further
comprising placing the at least one cutting element in cutting
engagement with another portion of the sidewall of the pilot hole
located axially on a side of the gage pad opposite an earth-boring
drill bit connected to the reamer by a drill string before placing
the gage pad in sliding contact with the portion of the sidewall of
the pilot hole.
[0061] While certain illustrative embodiments have been described
in connection with the figures, those of ordinary skill in the art
will recognize and appreciate that the scope of this disclosure is
not limited to those embodiments explicitly shown and described in
this disclosure. Rather, many additions, deletions, and
modifications to the embodiments described in this disclosure may
be made to produce embodiments within the scope of this disclosure,
such as those specifically claimed, including legal equivalents. In
addition, features from one disclosed embodiment may be combined
with features of another disclosed embodiment while still being
within the scope of this disclosure, as contemplated by the
inventors.
* * * * *